Novak Djokovic moved into the quarterfinals of the Shanghai Masters on Thursday with a 6—3, 6—3 win over Feliciano Lopez of Spain.

The second—seeded Serb had 12 aces and won 27 of 29 first—serve points. The third game of the second set was the only time in the match that Djokovic lost two points on serve.

“I’m trying to enjoy the efficiency of my serve,” said Djokovic, who had three aces in one game in the first set. “I’m not very well known around the tour for big serving. But so far in this tournament, and also in Beijing, it has been working very well for me. It has been giving me a lot of free points, a lot of confidence into the matches.”

Fourth-seeded Tomas Berdych of the Czech Republic defeated Sam Querrey of the United States 6—2, 6—7 (3), 6—4, and fifth—seeded Jo—Wilfried Tsonga beat Marcos Baghdatis of Cyprus 6—2, 7—6 (2).

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